Lighting unit for a helmet



FIG. 1 is a perspective view of a lighting unit for a helmet showing my new design;

FIG. 2 is a back view thereof; and,

FIG. 3 is a side view thereof.

The broken line showing represents unclaimed portions of the article and forms no part of the claimed design. 

CLAIM The ornamental design for a lighting unit for a helmet, as shown and described. 